Answer:
Explanation:
The equation is given as:
CH3CHOHC2H4CHO + CH3OH --> CYCLIC ACETAL + H2O
This above equation is carried out in the presence of a strong acid. There are five mechanisms employed and they are:
Step 1:
Initial formation of the hemiacetal which takes several steps
Step 2:
Addition of a proton. The hemicetal is protonated on the hydroxyl group (-OH group)
Step 3:
As seen a bond is broken to give the H2O molecule and a resonance stabilized cation.
The carbonyl group on the cation is enriched with the oxygen-18 got from the H2O molecule as seen in the mechanism.
Step 4:
An attraction occurs between electrophile and nucleophile i.e the stabilised cation and the lone paids of the methanol.
Step 5:
Finally, a proton (+) is removed from the molecule by a lone pair of electron on the methanol.
Attached are the Steps 1 - 5 mechanism below
Answer:
D. How frequently do earthquakes occur in San Francisco?
Answer: 4.04 ounce
Explanation: Given: Peanut butter contained in the jar = 1.43 kg
Used Peanut butter=8.0 % of 1.43kg = 
As we know 

Answer:
Please see Explanation and Attachment (Heating Curve for Water)
Explanation:
Energy change associated with phase change in substances is either endothermic (energy added to system) or exothermic (energy removed from system). Condensation is but one term in six (6) describing phase change occurring when energy change is involved. The following table, in general, summarizes the related effects of energy change as applied to phase change.
Process Phase Change Energy Change*
Condensation gas => liquid Exothermic
Evaporation liquid => gas Endothermic
Freezing liquid => solid Exothermic
Melting solid => liquid Endothermic
Sublimation solid => gas Endothermic
Deposition gas => solid Exothermic
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* Energy Change terms:
Endothermic => Addition of heat energy
Exothermic => Removal of heat energy